The invention relates to an internal combustion engine using several kinds of fuels with electronically adjustable intake and exhaust valves and injection device. This internal combustion engine can be used wherever engine drive units are required. It can be used as a drive for vehicles, cranes, excavators, etc in which the drive unit must be designed for different loads and must be able to use different kinds of fuel.
An internal combustion engine for using different types of fuel with electronically adjustable intake and exhaust valves on an electronically controllable injection device is already known from DE-OS Nos. 2,612,961 and 2,720,171.
These known electronically controlled internal combustion engines operate with a closed hydraulic circuit replacing the crankshafts hitherto conventionally used on such engines. This makes it possible to use a substantially electronic sequence control from the standpoint of minimizing the number of cylinders used and the partial recovery of the braking energy, whilst substantially replacing the gear. However, this known engine has the disadvantage of relatively expensive hydraulics which, particularly in the case of the construction of low power engines in large numbers, such as vehicle engines, increases the cost of production due to the use of hydraulic components. In addition, limits are placed on such an engine in the case of higher numbers of strokes or revolutions, because with higher flow rates in the hydraulic fluid the efficiency decreases due to internal friction.
In addition, an internal combustion engine is known in which the complete camshaft mechanism of a four-stroke Otto engine is replaced by a valve gear controlled by a microprocessor. Although this engine has the advantage of an electronically controlled valve mechanism, it has the decisive disadvantage of being linked with a costly crankshaft with a multicylinder arrangement. As a result of this crankshaft surface and the associated fixing to a top and bottom dead centre variable compression and the associated mixed Otto or diesel operation and the possibility of using different fuels in the same engine cannot be obtained. In addition, this known engine does not provide the possibility of substantially eliminating the gear and coupling with a braking energy recovery accumulator.